摘要
本文研究了一种基于反应热喷涂技术制备空心陶瓷微珠的方法与原理。以Al-CuO-Si-C为反应体系,基于传统火焰热喷涂原理和设备,熔射经团聚处理的自反应型复合粉体,使之在飞行过程中发生自蔓延高温合成反应,产生陶瓷雾化熔滴,采用温度可控的介质将其接收、冷却,使之快速凝固、结晶,从而获得中空结构、原位合成的空心陶瓷沉珠。实验结果表明,空心微珠以Cu-AlCu-SiC-莫来石等为主要组成相,为复相组织,表现为内部中空型(包括封闭中空和开口中空)和蜂窝型二种形式;Al-CuO间的系列自蔓延放热反应和高温火焰的辅助作用,形成陶瓷熔滴,C氧化反应产生的CO和CO2气体与有机物的高温汽化,在陶瓷熔滴快速凝固过程中遗留其中是空心陶瓷微珠形成的必要条件。
A method and preparation mechanism of hollow ceramic microspheres based on thermal reaction spraying technology was studied. According to A1-CuO-Si-C reactive system and the principle of traditional flame spraying as well as equipments, spraying polymerized compound powder and then producing ceramic fog droplet though SHS in the course of flying combustion, adopting a temperature-controlled media to receive, cooling to solidify and crystal rapidly, so that obtain hollow ceramic beads with character of hollow structure and insitu synthesis. The results show that hollow ceramic microspheres of Cu -Cu9Si - A1Cu - SiC - mullite as the diphase phase composition has been prepared and present two kinds of structure： open and closed. Ceramic droplets are formed by a series of A1 - CuO - Si - C self-propagating exothermic reaction and auxiliary role of high-temperature flame. The CO and CO2 gas produced by C oxidation reaction, left in ceramic droplet in rapid solidification process, is the necessary formation conditions of hollow ceramic microspheres.
出处
《热喷涂技术》
2012年第1期12-15,共4页
Thermal Spray Technology
关键词
反应热喷涂
空心陶瓷微珠
自蔓延高温合成
Thermal reaction spraying technology
Hollow ceramic microspheres
SHS technology
